Prehensor device and improvements of same

Abstract

A prehensor is provided comprising embodiments of a variable mechanical advantage mechanism, the prehensor including a first mechanical advantage for sizing an object, and a second mechanical advantage for gripping the object. Embodiments of the variable mechanical advantage mechanism include a brake assembly and multiple embodiments of a brakeless assembly. Additionally, multiple embodiments of a selectable voluntary opening/voluntary closing mechanism are provided, whereby a single prehensor can be switched back and forth between a voluntary closing mode and a voluntary opening mode. Additional embodiments include a safety clutch, an improved prehensor tendon, replaceable digits, and self decontaminating digits.

1. A prehensor device used for engaging an object, the prehensor device operated by a source of tensile force, the prehensor device comprising:
 (a) a base member; 
 (b) at least one longitudinal member engaging said base member; 
 (c) at least first and second digits, said first and second digits engaging said longitudinal member; 
 (d) a rotatable biasing member engaging at least one of (i) said first digit and (ii) said longitudinal member, wherein said biasing member comprises a bushing; and 
 (e) a tendon interconnected to the source of tensile force and said biasing member, wherein said tendon is interconnected to said bushing; 
 wherein, to provide a first mechanical advantage, at least a first tension is applied using the source of tensile force to rotate said biasing member and said first digit whereby the object is sized between said first and second digits, wherein, to provide a second mechanical advantage, at least a second tension is applied using the source of tensile force to compress said biasing member, whereby a grip pressure is applied to the object, and wherein the first tension is less than the second tension. 
 
   
   
     2. The device as claimed in  claim 1 , wherein:
 said second digit comprises a locking axle; and 
 said tendon is interconnected to said first and second digits; and further comprising 
 (f) a rotatable locking member engaging said longitudinal member, wherein said locking member may be positioned for selectively choosing a voluntary closing mode or a voluntary opening mode; 
 wherein said locking member is placed in a first position for said voluntary closing mode, wherein said locking member secures said locking axle, wherein said first digit is separated from said second digit and said first tension is applied using the source of tensile force to rotate said biasing member and said first digit whereby the object is sized between said first and second digits; and 
 wherein said locking member is placed in a second position for said voluntary opening mode, wherein said first digit is substantially adjacent said second digit and a third tension is applied using the source of tensile force to separate said second digit from said first digit, and wherein the third tension is reduced to engage the object between the first and second digits. 
 
   
   
     3. The device as claimed in  claim 1 , further comprising:
 (f) a safety clutch interconnected to at least one of said first or second digits, the safety clutch comprising:
 (i) a first clutch member including a first contacting surface; 
 (ii) a second clutch member including a second contacting surface, said second clutch member fixedly secured to said longitudinal frame member, at least a portion of said first contacting surface communicating with said second contacting surface; 
 (iii) an adjustable connector for biasing said first clutch member against said second clutch member; and 
 (iv) a clutch biasing member operatively associated with said adjustable connector, wherein said adjustable connector further operates to adjust the bias force between said first contacting surface and said second contacting surface as applied by the clutch biasing member, wherein a minimum torque is needed to rotate said first clutch member relative to said second clutch member; 
 wherein, when a separation force is applied between the first and second digits, said first clutch member will rotate relative to said second clutch member when said separation force causes a reaction torque between said first clutch member and said second clutch member that exceeds said minimum torque. 
 
 
   
   
     4. The device as claimed in  claim 1 , wherein at least one of said first and second digits comprises:
 (f) a replaceable digit comprising:
 (i) a tang portion; and 
 (ii) a replaceable digit portion detachably interconnected to said tang portion. 
 
 
   
   
     5. The device as claimed in  claim 1 , wherein at least one of said first and second digits comprises a self-decontaminating material comprising a photo-catalytic agent. 
   
   
     6. The device as claim in  claim 1 , wherein said biasing member further comprises a coil spring. 
   
   
     7. A prehensor device used for engaging an object, the prehensor device operated by a source of tensile force, the prehensor device comprising
 (a) a base member; 
 (b) at least one longitudinal member engaging said base member; 
 (c) at least first and second digits, said first and second digits engaging said longitudinal member, said first digit comprising a locking axle; 
 (d) a tendon interconnected to the source of tensile force and to said first and second digits; and 
 (e) a rotatable locking member engaging said longitudinal member, wherein said locking member may be positioned for selectively choosing a voluntary closing mode or a voluntary opening mode; 
 wherein said locking member is placed in a first position for said voluntary closing mode, wherein said locking member secures said locking axle, wherein said first digit is separated from said second digit and a first tension is applied using the source of tensile force to close said second digit against at least one of (i) said first digit and (ii) the object; and 
 wherein said locking member is placed in a second position for said voluntary opening mode wherein said first digit is substantially adjacent said second digit and a second tension is applied using the source of tensile force to separate said second digit from said first digit, and wherein the second tension is reduced to engage the object between the first and second digits. 
 
   
   
     8. The device as claimed in  claim 7 , further comprising:
 (f) a rotatable biasing member engaging at least one of (i) said second digit and (ii) said longitudinal member, wherein said tendon is interconnected to said biasing member; 
 wherein, to provide a first mechanical advantage, at least a first tension is applied using the source of tensile force to rotate said biasing member and said second digit whereby the object is sized between said first and second digits, wherein, to provide a second mechanical advantage, at least a second tension is applied using the source of tensile force to compress said biasing member, whereby a grip pressure is applied to the object, and wherein the first tension is less than the second tension. 
 
   
   
     9. The device as claimed in  claim 8 , wherein said biasing member comprises a bushing, wherein said tendon is interconnected to said bushing. 
   
   
     10. The device as claimed in  claim 8 , wherein said biasing member further comprises a coil spring. 
   
   
     11. The device as claimed in  claim 7 , further comprising:
 (f) a safety clutch interconnected to at least one of said first or second digits, the safety clutch comprising:
 (i) a first clutch member including a first contacting surface; 
 (ii) a second clutch member including a second contacting surface, said second clutch member fixedly secured to said longitudinal frame member, at least a portion of said first contacting surface communicating with said second contacting surface; 
 (iii) an adjustable connector for biasing said first clutch member against said second clutch member; and 
 (iv) a clutch biasing member operatively associated with said adjustable connector, wherein said adjustable connector further operates to adjust the bias force between said first contacting surface and said second contacting surface as applied by the clutch biasing member, wherein a minimum torque is needed to rotate said first clutch member relative to said second clutch member; 
 wherein, when a separation force is applied between the first and second digits, said first clutch member will rotate relative to said second clutch member when said separation force causes a reaction torque between said first clutch member and said second clutch member that exceeds said minimum torque. 
 
 
   
   
     12. The device as claimed in  claim 7 , wherein at least one of said first and second digits comprises:
 (f) a replaceable digit comprising:
 (i) a tang portion; and 
 (ii) a replaceable digit portion detachably interconnected to said tang portion. 
 
 
   
   
     13. The device as claimed in  claim 7 , wherein at least one of said first and second digits comprises a self-decontaminating material comprising photo-catalytic agent. 
   
   
     14. The device as claimed in  claim 7 , further comprising:
 (f) a brake member engaging said longitudinal member, said brake member comprising a pulley rotatable about an axle interconnected to said brake member, wherein said tendon engages said brake member; and 
 (g) an input cable interconnected to said source of tensile force and engaging said pulley; 
 wherein, to provide a first mechanical advantage, said locking member is placed in said first position and said first tension applied using the source of tensile force pulls said input cable and causes said brake member to rotate relative to said longitudinal member while said pulley remains substantially stationary relative to said brake member whereby said tendon is pulled and said second digit is rotated for sizing the object between said first and second digits, and wherein, to provide a second mechanical advantage, at least a third higher tension is applied using the source of tensile force pulling said input cable and causing said pulley to rotate relative to said brake member while said brake member remains substantially stationary relative to said longitudinal member whereby a grip pressure is applied to the object. 
 
   
   
     15. The device as claimed in  claim 7 , wherein said locking member further comprises a pocket for securing said locking axle. 
   
   
     16. A prehensor device used for engaging an object, the prehensor device operated by a source of tensile force, the prehensor device comprising:
 (a) a base member; 
 (b) at least one longitudinal member engaging said base member; 
 (c) at least first and second digits, said first and second digits engaging said longitudinal member, said second digit comprising a locking axle; 
 (d) a rotatable biasing member engaging at least one of (i) said first digit and (ii) said longitudinal member; and 
 (e) a tendon interconnected to the source of tensile force and said biasing member, wherein said tendon is interconnected to said first and second digits; 
 wherein, to provide a first mechanical advantage, at least a first tension is applied using the source of tensile force to rotate said biasing member and said first digit whereby the object is sized between said first and second digits, wherein, to provide a second mechanical advantage, at least a second tension is applied using the source of tensile force to compress said biasing member, whereby a grip pressure is applied to the object, and wherein the first tension is less than the second tension; 
 (f) a rotatable locking member engaging said longitudinal member, wherein said locking member may be positioned for selectively choosing a voluntary closing mode or a voluntary opening mode; 
 wherein said locking member is placed in a first position for said voluntary closing mode, wherein said locking member secures said locking axle, wherein said first digit is separated from said second digit and said first tension is applied using the source of tensile force to rotate said biasing member and said first digit whereby the object is sized between said first and second digits; and 
 wherein said locking member is placed in a second position for said voluntary opening mode, wherein said first digit is substantially adjacent said second digit and a third tension is applied using the source of tensile force to separate said second digit from said first digit, and wherein the third tension is reduced to engage the object between the first and second digits. 
 
   
   
     17. The device as claimed in  claim 16 , wherein at least one of said first and second digits comprises:
 (g) a replaceable digit comprising:
 (i) a tang portion; and 
 (ii) a replaceable digit portion detachably interconnected to said tang portion. 
 
 
   
   
     18. The device as claimed in  claim 16 , wherein at least one of said first and second digits comprises a self-decontaminating material comprising a photo-catalytic agent. 
   
   
     19. A prehensor device used for engaging an object, the prehensor device operated by a source of tensile force, the prehensor device comprising:
 (a) a base member; 
 (b) at least one longitudinal member engaging said base member; 
 (c) at least first and second digits, said first and second digits engaging said longitudinal member; 
 (d) a rotatable biasing member engaging at least one of (i) said first digit and (ii) said longitudinal member; and 
 (e) a tendon interconnected to the source of tensile force and said biasing member; 
 wherein, to provide a first mechanical advantage, at least a first tension is applied using the source of tensile force to rotate said biasing member and said first digit whereby the object is sized between said first and second digits, wherein, to provide a second mechanical advantage, at least a second tension is applied using the source of tensile force to compress said biasing member, whereby a grip pressure is applied to the object, and wherein the first tension is less than the second tension; 
 (f) a safety clutch interconnected to at least one of said first or second digits, the safety clutch comprising:
 (i) a first clutch member including a first contacting surface; 
 (ii) a second clutch member including a second contacting surface, said second clutch member fixedly secured to said longitudinal frame member, at least a portion of said first contacting surface communicating with said second contacting surface; 
 (iii) an adjustable connector for biasing said first clutch member against said second clutch member; and 
 (iv) a clutch biasing member operatively associated with said adjustable connector, wherein said adjustable connector further operates to adjust the bias force between said first contacting surface and said second contacting surface as applied by the clutch biasing member, wherein a minimum torque is needed to rotate said first clutch member relative to said second clutch member; 
 
 wherein, when a separation force is applied between the first and second digits, said first clutch member will rotate relative to said second clutch member when said separation force causes a reaction torque between said first clutch member and said second clutch member that exceeds said minimum torque. 
 
   
   
     20. The device as claimed in  claim 19 , wherein at least one of said first and second digits comprises:
 (g) a replaceable digit comprising:
 (i) a tang portion; and 
 (ii) a replaceable digit portion detachably interconnected to said tang portion. 
 
 
   
   
     21. The device as claimed in  claim 19 , wherein at least one of said first and second digits comprises a self-decontaminating material comprising a photo-catalytic agent.